A payment terminal can include one or more chips and subsystems that interact with payment devices such as a payment card having a magnetic strip that is swiped in a magnetic reader of the payment terminal, a payment device having a Europay/Mastercard/Visa (EMV) chip that is inserted into a corresponding EMV slot of the payment terminal, and near field communication (NFC) enabled devices such as a smartphone or EMV card that is tapped at the payment terminal and transmits payment information over a secure wireless connection. In order to ensure accurate processing of payment transactions, proper communication of signals between elements of the chips in the payment terminal is required. Merchants and consumers attempting to complete a payment transaction may become frustrated if errors occur during payment transactions or the payment transactions are not otherwise processed accurately due to unstable or inaccurate operation of the chips in the payment terminal.
Different subsystems of a payment device may operate at different voltage levels. In some instances, each of the subsystems may require periodic signals for operation, for example, in order to communicate. It may be desired that different components, chips, and subsystems having different operating voltages are able to communicate or otherwise interact with each other, or that components from one chip, component, or subsystem be able to provide signals for use in other components. Conventional techniques for allowing interactions of this sort may have problems that occur, for example, if a level shift operation is attempted. One problem is that the low voltage from one chip, component, or subsystem may not be enough to create a similar signal elsewhere using conventional techniques. In addition, some techniques for shifting periodic signals may result in asymmetric rising and falling times, which may alter the duty cycle of the signal.